Magnets | Science Museum Group Collection

Du Bois-Reymond's compensating magnet. It allowed the one operating a galvanometer to fine-tune its sensitivity by repositioning a permanent magnet as necessary in order to compensate wholly or partially for the Earth's magnetic pull on the galvanometer needle. The wooden guide was affixed to the center of the galvanometer and could rotate freely; the magnet, in a brass mount, could be precisely positioned at any distance from the center. A pulley and string arrangement allowed the operator to adjust the magnet on the fly while seated a distance away at the reading telescope.

Du Bois-Reymond's galvanometer-compensating magnet

1876

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Eclipse laboratory set of permanent magnets

Firle eye magnet in case

Set of 'Artificial' Magnets, c. 1762

Magnets with quote by Stephen Hawking

Portable pivoted horse-shoe magnet type galvanometer

Two ferrite loudspeaker ring magnets

Magnet rotating on its own axis

Magnets rotating round a current

Large magnet

Magnetic disc record type 3011 made by W. Assman at Bad Homburg

Magnet, cuboid block, magnets on base

Pair of collimator magnets, ex Kew Observatory

Short steel bar magnet

Bar magnets

Pair of magnetic floater magnets

Horseshoe magnet 170mm long

Magnet in case

Pair of bar magnets

Collection of six ball-ended magnets

Pair of bar magnets

Four pairs of small steel magnets

Magnetical magazine, twelve magnets in case

Two pairs of bar magnets with keepers in fitted box

Selection of permanent magnets

Pair of collimator magnets in wooden carier

Short steel bar magnet

Magnet to show construction

2 steel horseshoe magnets

Magnet, metal, U-shaped, European, 19th century

Short steel bar magnet

Pair of bar magnets

Horseshoe magnet 210mm long

Professor Daniell's lodestone used by Faraday in 1831

Du Bois-Reymond's galvanometer-compensating magnet

Magnetic disc record type Universa 50

Motor car magneto

1931 design: 'four claw' cobalt steel permanent magnet

1931 design 'M' shape cobalt steel permanent magnet

Three bar magnets

1931 design 'enclosed pot' cobalt steel permanent magnet

1931 design 'assembled' cobalt steel permanent magnet

Two bar magnets with pair of keeps in wooden box

Sherardised magnet

C.A.V., HN4, 4 cylinder magnet

Magnet, in wooden case used by linemen for resetting early telegraph instruments

Four coil resistive magnet (0.1 Tesla) used in MRI